Spider venom could be natural viagra!

A toxin synthesized from the venom of a spider may offer an alternative to today''s erectile dysfunction drugs, say researchers.

A toxin synthesized from the venom of a spider may offer an alternative to today''s erectile dysfunction drugs, say researchers.

In the new study, published online Aug. 23 in the Journal of Sexual Medicine, the toxin, unpoetically named PnTx2-6, reverses age-related erectile dysfunction in mice.

It comes from the bite of the Brazilian wandering spider (Phoneutria nigriventer).

A bite from a wandering spider is very painful and male victims may even find themselves with priapism, or unrelenting and painful erection.

It was this symptom, turning up in emergency rooms after spider bites in Brazil, that first alerted researchers to the potential of PnTx2-6 as an erectile dysfunction (ED) drug.

The toxin has been shown to improve erections in rats with hypertension and diabetes.

Now, researchers have tested it in aging mice and found that the toxin is effective in reversing age-related ED as well.

"It''s working in aging, which is a natural process," study researcher Kenia Nunes, a physiologist at Georgia Health Sciences University, told LiveScience.

Viagra, Levitra and other ED drugs on the market work by inhibiting an enzyme called PDE5.

To get an erection, a man''s body must release nitric oxide, which relaxes the smooth muscle around the arteries of the penis, allowing for his blood vessels to dilate.

The nitric oxide is a first step in a series of chemical reactions that allow this muscle relaxation to take place. One step in the series is cGMP, a signaling molecule that acts to keep the muscles relaxed.